Multiple throttle apparatus

ABSTRACT

According to the present apparatus, there are provided a first throttle body  10  and a second throttle body  10  that define multiple intake passages corresponding to arranged cylinders on one side and on the other side of a V-type engine respectively, a first throttle shaft  31  that simultaneously opens/closes the multiple throttle valves  20  disposed in the first throttle body  10 , and a second throttle shaft  32  that simultaneously opens/closes the multiple throttle valves  20  disposed in the second throttle body  10 , and a motor  52  and a gear train  52   a,    53  to  57  are employed as drive means  50  that rotatably drives the first throttle shaft  31  and the second throttle shaft  32 . Consequently, open/close operations are synchronously carried out without generating a phase shift. Electronic control is provided for multi-throttle apparatuses applied to V-type engines of two-wheeled vehicles and the like, and the synchronization among throttle valves is secured.

TECHNICAL FIELD

The present invention relates to a multi-throttle apparatus whichsynchronously opens/closes a large number of throttle valves disposed inintake passages of a V-type engine, and more particularly relates to amulti-throttle apparatus including throttle valves respectively disposedin intake passages for respective cylinders of a V-type engine installedon two-wheeled vehicles and the like.

BACKGROUND ART

A throttle apparatus of dual cable/electronic control type, and athrottle apparatus of single electronic control type, for example, havebeen known as conventional throttle apparatuses applied to enginesinstalled on four-wheeled vehicles.

For example, on an intake system provided with two surge tanks which areused to combine each three intake passages corresponding to respectivecylinders on a V-type six-cylinder engine, and intake passages extendingupstream from the respective surge tanks, the conventionaldual-cable/electronic-controlled throttle apparatus interlocks twothrottle valves with each other, which are disposed in the respectiveupstream intake passages, by means of a single throttle shaft, therebydriving the throttle valves to be opened/closed by means of a cable or amotor (refer to patent document 1, for example).

The conventional electronic-controlled throttle apparatus rotatablycombines the throttle valves, which are disposed respectively in the twointake passages formed on the throttle body, by means of a singlethrottle shaft, thereby driving the throttle valves to be opened/closedby means of a motor disposed on one end of the throttle shaft (refer topatent document 2, for example).

The above-mentioned conventional apparatus is disposed upstream of thesurge tanks or upstream of the relatively long intake passages, and theintake air controlled by the opening/closing action of the throttlevalves is once accumulated in the surge tanks, or passes through thelong intake passages, and is then flowed through the intake passagescorresponding to the respective cylinders. Thus, a change in the intakeair quantity due to a small variation of the opening/closing operationsof the throttle valves, a displacement from the synchronization of thetwo throttle valves, and the like do not pose serious problems.

On the other hand, as throttle apparatuses for V-type engines installedon two-wheeled vehicles and the like, due to the responsiveness to athrottle operation being emphasized, there has been known amulti-throttle apparatus where throttle valves are disposed respectivelyin intake passages corresponding to the respective cylinders (intakeports) at a location close to the intake port of a cylinder head,throttle shafts rotatably supporting the respective throttle valves areconnected by a synchronization lever, an energizing spring, and the likeused for a transmission of the torque, the throttle shafts on the bothbanks disposed corresponding to the respective arranged cylinders in theV shape are further interlocked via a link mechanism or the like, and asingle cable is used to drive all the throttle valves to beopened/closed. In addition, on this apparatus, an independent ISC valveis provided to carry out idle speed control (ISC) of the engine.

[Patent document 1]

Japanese Laid-Open Patent Publication (Kokai) No. H6-207535

[Patent document 2]

Japanese Laid-Open Patent Publication (Kokai) No. H8-218904

It has been studied to provide electronic control which drives multiplethrottle valves by means of a motor, and further, control of the idlespeed by finely adjusting the opening angle of the throttle valveswithout an independent ISC valve also on V-type engines installed ontwo-wheeled vehicles and the like. In addition, the throttle operationon the two-wheeled vehicles is more sensitive than that on four-wheeledvehicles, and is accompanied by rapid changes, and there are thusrequired a precision in the synchronization corresponding to thesensitivity, high responsiveness following the rapid changes, and thelike.

If the above-mentioned conventional throttle apparatuses forfour-wheeled vehicles are applied as a throttle apparatus fortwo-wheeled vehicles and the like, the responsiveness is inferior, andthe practicality lacks. Namely, on these apparatuses, a middle portionof the throttle shaft is directly supported by through holes on thethrottle bodies or brackets, the friction resistance is thus large onsliding parts, and due to influence of a resistive force of the intakeair received by the throttle valves caused by the rapid change, themoment of inertia of the throttle valves, and the like, the throttleshaft may be brought in close contact with the through holes to generatea stick and the like, or the throttle shaft may generate torsion tocause mutual displacements from the synchronization among the throttlevalves and the like.

In addition, if a motor is simply installed on the conventionalmulti-throttle apparatus for two-wheeled vehicles, and electroniccontrol is intended while the rotation angle of the throttle shaft isused as a control parameter, mutual slight displacements from thesynchronization (phase shift) among the throttle valves and the like,which are permitted in the conventional cable control, cause obstructionin the realization of the electronic control. Especially, it isnecessary to surely prevent the displacements from the synchronizationfor the control in the case of carrying out the idle speed control bymeans of the throttle valves without the ISC valve.

The present invention is devised in view of the problems of theabove-mentioned prior art, and has an object of providing amulti-throttle apparatus which, upon driving multiple throttle valvesrespectively disposed in intake passages to be opened/closed, isexcellent in responsiveness to rapid changes while synchronizing therespective throttle valves, integrates components, reduces the size, andis preferable for high-performance V-type engines installed especiallyon two-wheeled vehicles and the like.

DISCLOSURE OF THE INVENTION

A multi-throttle apparatus according to the present invention includinga first throttle body that defines multiple intake passagescorresponding to arranged cylinders on one side of a V-type engine and asecond throttle body that defines multiple intake passages correspondingto arranged cylinders on the other side thereof, multiple throttlevalves disposed respectively in the multiple intake passages, a firstthrottle shaft that supports the multiple throttle valves disposed inthe first throttle body to be simultaneously opened/closed, a secondthrottle shaft that supports the multiple throttle valves disposed inthe second throttle body to be simultaneously opened/closed, drive meansthat rotatably drives the first throttle shaft and the second throttleshaft, and return springs that return the throttle valves to apredetermined angular position, is configured such that the drive meansincludes a motor disposed between the first throttle shaft and thesecond throttle shaft, and a gear train that transmits the driving forceof the motor to the first throttle shaft and the second throttle shaft,and the first throttle body and the second throttle body includebearings that respectively support the first throttle shaft and thesecond throttle shaft in mutual intervals of the multiple intakepassages.

With this configuration, if the motor drives the throttle shafts, thefirst throttle shaft for the arranged cylinders on the one side and thesecond throttle shaft for the arranged cylinders on the other siderotate simultaneously, the multiple throttle valves supported by therespective throttle shafts turn to carry out the open operation againstthe energizing forces of the return springs, and, on the other hand, ifthe motor stops, the energizing forces of the return springs cause areverse rotation to carry out the close operation.

On this occasion, since the first throttle shaft and the second throttleshaft are interlocked with each other through the gear train, no phaseshift is generated compared with a case where a link mechanism or thelike is used, and the synchronization between them is thus secured. Therespective throttle valves thus are synchronized without generating aphase shift, follow rapid changes, and operate smoothly.

Moreover, since the motor is disposed between the first throttle shaftand the second throttle shaft, the apparatus can be integrated while thedistribution of the driving force is equalized, and both of the throttleshafts are supported by the bearings in the mutual intervals between theintake passages, the torsions of both of the throttle shafts are surelyprevented, the respective throttle valves are synchronouslyopened/closed without generating a phase shift, properly follow rapidchanges respectively, and operate smoothly.

The above-mentioned configuration may employ such a configuration thatthe gear train is disposed on ends on the same side of the firstthrottle shaft and second throttle shaft.

With this configuration, the drive means can be integrated on the oneside of the apparatus, and the width and the size of the entireapparatus can be reduced.

The above-mentioned configuration may employ such a configuration thatthe gear train includes a gear train that transmits the driving force ofthe motor to one end of the first throttle shaft, and a gear train thatinterlocks the second throttle shaft with the first throttle shaft onthe other end of the first throttle shaft.

With this configuration, since the driving force is transmitted to thefirst throttle shaft and the second throttle shaft equally on the leftand right sides, the transmission loss of the torque can be reduced. Ifboth of the throttle shafts are driven in the mutually oppositedirections, it is possible to eliminate gears such as an idler.

The above-mentioned configurations may employ such a configuration thatthe throttle bodies (first throttle body and second throttle body)include multiple throttle bodies that respectively define the multipleintake passages, and are connected to each other in the direction inwhich the throttle shafts (first throttle shaft and second throttleshaft) extend, and the multiple throttle bodies include an engagementsection that engages the bearing.

With this configuration, it is possible to readily dispose the bearingsin the mutual intervals between the intake passages by connecting therespective throttle bodies after the bearings are engaged with theengagement sections, thereby forming the first throttle body and thesecond throttle body.

The above-mentioned configuration may employ such a configuration thatthe multiple throttle bodies are connected with each other via a spacerthat adjusts the mutually separated distance.

With this configuration, even if the mutual distances between the enginecylinders (intake ports) are different from each other, themulti-throttle apparatus can be readily configured corresponding tovarious engines by properly adjusting the length of the spacers.

The above-mentioned configuration may employ such a configuration thatthe spacers are formed so as to fix the bearings to the throttle bodies.

With this configuration, it is not necessary to employ a dedicatedcomponent used to fix the bearings, thereby simplifying the structure.

The above-mentioned configurations may employ such a configuration thatthe multiple throttle valves are formed such that the cross sectionthereof tapers off to the tip thereof as departed from the rotationcenter.

With this configuration, the moments of inertia of the throttle valvesdecrease, and the response to rapid changes increases, and the torsionof the throttle shafts is prevented more surely.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view showing an embodiment of a multi-throttleapparatus according to the present invention;

FIG. 2 is a side view showing drive means of the apparatus shown in FIG.1;

FIG. 3 is a plan sectional view showing a periphery of throttle shaftsand throttle valves of the apparatus shown in FIG. 1;

FIG. 4 is a side sectional view showing the throttle valves of theapparatus shown in FIG. 1;

FIG. 5 is a plan view showing another embodiment of the multi-throttleapparatus according to the present invention;

FIG. 6 is a side view showing drive means of the apparatus shown in FIG.5; and

FIG. 7 is a plan sectional view showing a periphery of throttle shaftsand throttle valves of the apparatus shown in FIG. 5.

BEST MODE FOR CARRYING OUT THE INVENTION

A description will now be given of embodiments of the present inventionwith reference to accompanying drawings.

FIGS. 1 to 4 show an embodiment of a multi-throttle apparatus accordingto the present invention, FIG. 1 is plan view showing the schematicconfiguration, FIG. 2 is a side view of drive means, FIG. 3 is a plansectional view showing a periphery of throttle shafts, and FIG. 4 is aside sectional view showing throttle valves.

This apparatus is a four-throttle apparatus applied to a V-typefour-cylinder engine installed on two-wheeled vehicles, and, as shown inFIG. 1, is provided with two throttle bodies 10 that define intakepassages 11, and form a first throttle body attached to arrangedcylinders on the left side (one side), two throttle bodies 10 that forma second throttle body attached to arranged cylinders on the right side(the other side), four throttle valves 20 that are disposed in therespective intake passages 11, a first throttle shaft 31 that rotatablysupports the two throttle valves 20 disposed in the first throttle bodyso as to simultaneously close/open them, a second throttle shaft 32 thatrotatably supports the two throttle valves 20 disposed in the secondthrottle body so as to simultaneously close/open them, bearings 40 thatrespectively and rotatably support both the throttle shafts 31, 32,drive means 50 that applies a rotational driving force to the throttleshafts 31, 32, return springs 60 that return the throttle valves 20 to apredetermined angular position, spacers 70 that are disposed in themutual intervals between the throttle bodies 10, connection frames 80that connect the four throttle bodies 10, an angle detection sensor 90that detects the rotation angle of the second throttle shaft 32, and thelike.

The throttle body 10 is molded by means of die forming using an aluminummaterial or resin material, and, as shown in FIG. 1 to FIG. 3, is formedby the intake passage 11 that has an approximately circular section,through holes 12 that pass the throttle shaft 31 or 32, engagementsections 13 in a recessed shape that engage the bearings 40, jointprotrusions 14, and the like.

The through holes 12 are formed slightly larger than the outer diameterof the throttle shafts 31, 32 to achieve a non-contact state, and thethrottle shafts 31, 32 are supported only by the bearings 40.

The throttle valve 20 is molded by means of die forming using analuminum material or resin material, and, as shown in FIG. 4, is formedsuch that the cross section thereof tapers off to the tip thereof asdeparted from the rotation center C increases. The throttle valves 20are fixed to the throttle shafts 31, 32 by means of screws or the like.

Forming the throttle valves 20 in the shape tapering off to the tip inthis way reduces the moment of inertia, increases the responsiveness ofthe opening/closing operations, and contributes to the prevention of thetorsion of the throttle shafts 31, 32.

As shown in FIG. 3, the bearings 40 are engaged with the engagementsections 13 of the throttle bodies 10, are disposed on both sides mutualintervals between the intake passages 11 (in the areas of the spacers70).

Even if a resistive force of the intake air generated by the rapidopening/closing operations and the like is applied to deflect middleareas of the throttle shafts 31, 32 via the throttle valves 20, forexample, since the middle areas are supported by the bearings 40, asmooth rotation is provided without generating a stick and the like.

Consequently, the torsion of the throttle shafts 31, 32 and the like areprevented, and the synchronization of the throttle valves 20(opening/closing operations in phase) is secured.

Note that various bearings such as ball bearings, roller bearings, andcylindrical bearings whose contact face itself provides a bearingfunction, may be employed as the bearing 40. In addition, bearings whichprovide supports in the thrust direction in addition to the radialdirection are employed as at least a part of the multiple bearings 40.

As shown in FIGS. 1 to 3, the drive means 50 is disposed so as to applythe driving force to the ends on the same side of the first throttleshaft 31 and the second throttle shaft 32, and is formed by a holdingplate 51 that is fixed to the throttle bodies 10 and the connectionplate 80, a DC motor 52 that is disposed between the first throttleshaft 31 and the second throttle shaft 32, is fixed to the holding plate51, and includes a pinion 52 a, a gear train that includes a gear 53(large gear 53 a and small gear 53 b) that is rotatably supported by thesupporting plate 51, and meshes with the pinion 52 a, a gear 54 that isfixed to the first throttle shaft 31, and meshes with the gear 53 (smallgear 53 b), a gear 55 that is rotatably supported by the holding plate51, and meshes with the pinion 52 a, a gear 56 (large gear 56 a andsmall gear 56 b) that meshes with the gear 55, a gear 57 that is fixedto the second throttle shaft 32, and meshes with the gear 56 (small gear56 b), and the like.

Namely, if the DC motor 52 rotates, the rotational driving force thereofis transmitted from the pinion 52 a to the first throttle shaft 31 viathe gears 53, 54, and is transmitted from the pinion 52 a to the secondthrottle shaft 32 via the gears 55, 56, 57, and the first throttle shaft31 and the second throttle shaft 32 rotate in the mutually oppositedirections to drive the throttle valves 20 to be opened/closed.

Since the driving force is transmitted via the gear train in this way,compared with a case where the transmission is carried out via a linkmechanism or the like, a phase shift between both the throttle shafts31, 32 is prevented, the mutual synchronization of the throttle valves20 supported by the throttle shafts 31, 32 is secured, and the fourthrottle valves 20 carry out the open/close operations in phase.

Moreover, the arrangement of the drive means 50 on the one end of theapparatus, especially the arrangement of the DC motor 52 between thefirst throttle shaft 31 and the second throttle shaft 32, integrates thedrive means 50, thereby integrating the apparatus, and thus reducing thewidthwise dimension, especially restraining protrusions in the widthwisedirection upon being installed on a two-wheeled vehicle, and it is thuspossible to prevent the apparatus from hitting the ground and the likeupon the vehicle falling and the like, and consequently being damaged.

It should be noted that on the holding plate 51 is provided an adjustscrew 58 which restricts a stop position of the gear 54, namely a restposition of the throttle valves 20, and an appropriate adjustment of theadjust screw 58 sets the opening of the throttle valves 20 in the reststate to a desired value.

The return springs 60 are torsion springs disposed around the spacers 70as shown in FIG. 3, and apply a rotational energizing force to thethrottle shafts 31, 32 to return the throttle valves 20 to thepredetermined angular position. It should be noted that the returnsprings 60 may be disposed close to the drive means 50. In this case,the energizing forces are applied close to the driving force, thetorsion of the respective throttle shafts 31, 32 is prevented as much aspossible, and the mutual synchronization of the throttle valves 20supported by the respective throttle shafts 31, 32 is secured.

Although only one spring is used for the respective throttle shafts 31,32 as the return spring 60 in this case, multiple return springsgenerating energizing forces different from each other may be disposedalong the respective throttle shafts 31, 32, a return spring whichapplies the largest energizing force may be disposed close to thelocation to which the driving force is applied, and the other returnsprings may be disposed so as to gradually decrease the energizing forcetoward the other end of the throttle shafts 31, 32. In this case, thetorsion of the throttle shafts 31, 32 is prevented, and the returnoperation becomes smoother.

The spacers 70 connect the throttle bodies 10 with each other in theextension direction of the throttle shafts 31, 32 as shown in FIG. 3.The spacers 70 are formed into a cylindrical shape, and include jointrecesses 71 that engage the joint protrusions 14 of the throttle bodies10, a through passage 72 that passes the throttle shaft 31 or 32 withoutcontact, positioning sections (not shown) that mutually position thejoined throttle bodies 10, and the like. The end surfaces of the throughpassage 72 are formed to push and fix the bearings 40 engaged to theengagement sections 13. An independent component used to fix the bearing40 is thus not necessary.

If the spacer 70 is used to connect the throttle bodies 10 with eachother, the bearings 40 are first installed to the engagement sections 13of the throttle bodies 10, the throttle bodies 10 are then mutuallyjoined and connected on both sides of the spacer 70, and the connectionplate 80 firmly fixes the throttle bodies 10 to each other.

On this occasion, a proper change of the length of the spacer 70 enablesapplication to various engines different in the mutual separateddistance between the intake passages 11.

The angle detection sensor 90 is a non-contact angle sensor disposed onthe end of the second throttle shaft 32 as shown in FIG. 1 and FIG. 3,detects the rotation angle position of the second throttle shaft 32(namely the rotation angle position of the throttle valves 20), andoutputs a resulting detection signal to a control unit. The control unittransmits a drive signal to the DC motor 52 based on the detectionsignal, and controls the opening of the throttle valves 20 according toa control mode.

A description will now be given of the operation of the above-mentionedmulti-throttle apparatus.

The DC motor 52 rotates in one direction based on the control signaltransmitted from the control unit, and the rotational driving force istransmitted to the first throttle shaft 31 and the second throttle shaft32 via the gear train 52 a, 53, 54, and the gear train 52 a, 55, 56, 57.

The first throttle shaft 31 and the second throttle shaft 32 then startrotating in the mutually opposite directions against the energizingforces of the return springs 60, and the throttle valves 20 rotate fromthe rest position to the position to fully open the intake passages 11.

On this occasion, since the throttle shafts 31, 32 are supported by thebearings 40 in mutual intermediate areas between the intake passages 11as well, and the throttle valves 20 are further formed to taper off tothe tip thereof to decrease the moment of inertia, the throttle shafts31, 32 rotate smoothly, thereby preventing the torsion thereof.Consequently, the throttle valves 20 supported by the respectivethrottle shafts 31, 32 are synchronously opened/closed withoutgenerating mutual phase shifts.

On the other hand, if the DC motor 52 rotates in the opposite directionbased on the control signal from the control unit, the throttle shafts31, 32 rotate in the opposite direction while the energizing forces ofthe return springs 60 are applied, and the throttle valves 20 rotatefrom the fully open position to the rest position, which closes theintake passages 11. In the normal operation, the rotation of the DCmotor 52 is properly controlled according to the control mode, and thethrottle valves 20 are driven to be opened/closed to attain an optimalopening. If the DC motor 52 stops, the throttle shafts 31, 32 arequickly rotated by the energizing forces of the return springs 60 toreturn the throttle valves 20 to the rest position.

If the idle speed control is carried out by means of the throttle valves20, the DC motor 52 is properly driven based on the drive signal fromthe control unit, and the throttle shafts 31, 32, namely the opening ofthe throttle valves 20 is finely adjusted. Since the mutualsynchronization of the throttle valves 20 is secured upon carrying outthe ISC drive in this way, highly precise control is enabled.

FIG. 5 and FIG. 6 show another embodiment of the multi-throttleapparatus according to the present invention, and is the same as theabove-mentioned embodiment except that the disposition of the drivemeans 50 is changed. In the present embodiment, like components aredenoted by like numerals as of the above-mentioned embodiment, and willbe explained in no more details.

On this apparatus, as shown in FIG. 5 to FIG. 7, the driving force ofthe motor 52 is first transmitted to the first throttle shaft 31, and adriving force of the first throttle shaft 31 is then transmitted to thesecond throttle shaft 32.

Namely, on a section on the one side of the apparatus are disposed themotor 52 including the pinion 52 a, the gear 53, and the gear 54 that isfixed to the one end of the first throttle shaft 31. On a section on theother side of the apparatus are disposed a gear 56′ that is fixed to theother end of the first throttle shaft 31, and a gear 57′ that is fixedto one end of the second throttle shaft 32, and meshes with the gear56′.

On the other end of the second throttle shaft 32 (in a section on theone side of the apparatus) is disposed the angle detection sensor 90.

With this arranged configuration, the gear 55 serving as the idler inthe above-mentioned embodiment can be eliminated, thereby reducing thecorresponding number of the component items.

A description will now be given of the operation of the above-mentionedmulti-throttle apparatus.

If the DC motor 52 rotates in one direction based on a control signaltransmitted from a control unit, the rotational driving force is firsttransmitted to the first throttle shaft 31 via the gear train 52 a, 53,54, and the rotational force of the first throttle shaft 31 is thentransmitted to the second throttle shaft 32 via the gears 56′, 57′ onthe opposite side.

The first throttle shaft 31 and the second throttle shaft 32 then startrotating in the mutually opposite directions against the energizingforces of the return springs 60, and the throttle valves 20 rotate fromthe rest position to the position to fully open the intake passages 11.

With this configuration, since the driving force is transmitted to thefirst throttle shaft 31 and the second throttle shaft 32 equally on boththe sides, the transmission loss of the torque can be reduced.

As in the above-mentioned embodiment, since the throttle shafts 31, 32are supported by the bearings 40 in mutual intermediate areas betweenthe intake passages 11 as well, and the throttle valves 20 are furtherformed to taper off to the tip thereof to decrease the moment ofinertia, the throttle shafts 31, 32 rotate smoothly, thereby preventingthe torsion thereof. Consequently, the throttle valves 20 supported bythe respective throttle shafts 31, 32 are synchronously opened/closedwithout generating mutual phase shifts.

On the other hand, if the DC motor 52 rotates in the opposite directionbased on the control signal from the control unit, the first throttleshaft 31 rotates in the opposite direction, and the second throttleshaft 32 simultaneously rotates in the opposite direction in aninterlocking manner while the energizing forces of the return springs 60are applied, and the throttle valves 20 rotate from the fully openposition to the rest position, which closes the intake passages 11. Inthe normal operation, the rotation of the DC motor 52 is properlycontrolled according to the control mode, and the throttle valves 20 aredriven to be opened/closed to attain an optimal opening. If the DC motor52 stops, the throttle shafts 31, 32 are quickly rotated by theenergizing forces of the return springs 60 to return the throttle valves20 to the rest position.

Although the description is given of the four-throttle apparatus in theabove-mentioned embodiments as the multi-throttle apparatus, theconfiguration of the present invention is not limited to this example,and may be employed in multi-throttle apparatuses such as afive-throttle, where two throttles for the arranged cylinders on oneside and three throttles for the arranged cylinders on the other side,or six or more-throttle apparatus.

Although the spacers 70 are used to connect the multiple throttle bodies10 in the above-mentioned embodiments, the throttle bodies 10 may bedirectly joined for the connection without using the spacers 70.Although the description is given of the multiple throttle bodies 10formed independently, an integrally formed throttle bodies may beemployed as long as the bearings 40 can be fitted.

Further, although the description is given of the high-performanceV-type engines installed on the two-wheeled vehicles as the engines towhich the multi-throttle apparatus according to the present invention isapplied in the above-mentioned embodiments, the engines are not limitedto this type, and the present invention may be applied to V-type enginesinstalled on other vehicles such as automobiles.

INDUSTRIAL APPLICABILITY

As described above, with the multi-throttle apparatus according to thepresent invention, for the first throttle body and the second throttlebody disposed respectively for the arranged cylinders on the one sideand the arranged cylinders on the other side of a V-type engine, sincethe first throttle shaft and the second throttle shaft which rotatablysupport the throttle valves are synchronously driven by the drive meansincluding a motor and gear trains, the phase shift is reduced, and thesynchronization between them is secured compared with the case where alink mechanism or the like is used to drive. As a result, the respectivethrottle valves do not generate the phase shift, are synchronouslyopened/closed, and follow quick changes with proper responsiveness tooperate smoothly.

1. A multi-throttle apparatus comprising: a first throttle body thatdefines a plurality of intake passages corresponding to arrangedcylinders on one side of a V-type engine respectively; a second throttlebody that defines a plurality of intake passages corresponding toarranged cylinders on the other side thereof respectively; a pluralityof throttle valves disposed respectively in said plurality of intakepassages; a first throttle shaft that supports said plurality ofthrottle valves disposed in said first throttle body to besimultaneously opened/closed; a second throttle shaft that supports saidplurality of throttle valves disposed in said second throttle body to besimultaneously opened/closed; a drive means for rotatably driving saidfirst throttle shaft and said second throttle shaft; and a return springthat returns said throttle valves to a predetermined angular position,wherein said drive means comprises a motor disposed between said firstthrottle shaft and said second throttle shaft, and a gear train thattransmits a driving force of said motor to said first throttle shaft andsecond throttle shaft, and said first throttle body and said secondthrottle body include bearings which respectively support said firstthrottle shaft and said second throttle shaft in mutual intervalsbetween said plurality of intake passages.
 2. The multi-throttleapparatus according to claim 1, wherein said gear train is disposed onends on the same side of said first throttle shaft and said secondthrottle shaft.
 3. The multi-throttle apparatus according to claim 1,wherein said gear train comprises a gear train that transmits thedriving force of said motor to one end of said first throttle shaft, anda gear train that interlocks said second throttle shaft with said firstthrottle shaft on the other end of said first throttle shaft.
 4. Themulti-throttle apparatus according to claim 1, 2 or 3, wherein saidthrottle body comprises a plurality of throttle bodies that respectivelydefine said plurality of intake passages, and are connected to eachother in the direction in which said throttle shaft extends, and saidplurality of throttle bodies comprise an engagement section that engagessaid bearing.
 5. The multi-throttle apparatus according to claim 4,wherein said plurality of throttle bodies are connected with each othervia a spacer that adjusts the mutual separated distance.
 6. Themulti-throttle apparatus according to claim 5, wherein said spacer isformed so as to fix said bearing to said throttle body.
 7. Themulti-throttle apparatus according to claim 1 or 2, wherein saidplurality of throttle valves are formed such that the cross sectionthereof tapers off to the tip thereof as departed from the rotationcenter.
 8. The multi-throttle apparatus according to claim 4, whereinsaid plurality of throttle valves are formed such that the cross sectionthereof tapers off to the tip thereof as departed from the rotationcenter.
 9. The multi-throttle apparatus according to claim 5, whereinsaid plurality of throttle valves are formed such that the cross sectionthereof tapers off to the tip thereof as departed from the rotationcenter.
 10. The multi-throttle apparatus according to claim 6, whereinsaid plurality of throttle valves are formed such that the cross sectionthereof tapers off to the tip thereof as departed from the rotationcenter.